Are the numbers for frame and engine normally the same or just the same year?
I have checked the number on the frame and it is as I said, starting with B which suggests that the frame is 1957 whilst the engine is 1955. I guess that this will be important to a collector?.
There are several things that are not original anyway. I have converted to a 12 volt generator with electronic ignition and also designed and made the rear suspension which mounts to the shock-absorber as I was unable to find parts.
when I dismantled the engine, there was very little wear to the bore and the big-end bearing was also good. I fitted new piston rings and a new small-end bush and pin. I have not run the engine yet but will be in the next day or two so we will see.